Electrical devices such as electrical connectors typically have an electrical cable extending from the device. It is necessary to securely fasten the electrical cable to the electrical device to prevent the conductors from being pulled from their terminations, which can damage the conductors and the electrical device. In addition, pulling or tearing the electrical conductors from their terminations in the electrical device can result in the device becoming inoperable and can result in serious injury to the user due to shorting of the electrical current being carried in the conductors. Electrical connectors and other electrical devices typically include an assembly for clamping or otherwise securing the end of the electrical cable to the device. Electrical devices and in particular electrical connectors are primarily constructed for use with a standard size cable or a limited range of cable sizes. However, there are instances where cables smaller than the standard size are required. Thus, it is advantageous to have an electrical connector or other device that is able to accommodate different-sized electrical cables. Many of the electrical devices currently available are not able to effectively accommodate different-sized electrical cables.
Examples of such assemblies for securing a standard size electrical cable in a connector or other electrical device are disclosed in U.S. Pat. Nos. 2,911,616 to Townsend and 3,402,382 to De Tar. These devices generally include a threaded screw extending through an outer wall of the housing of the device to press the electrical cable against the opposite side of the housing. This arrangement has the disadvantage of being limited in the extent of the translational movement of the screw and thus limited in size of the electrical cable which can be secured. These devices do not always effectively grip electrical conductors of different sizes.
Another common construction of electrical devices includes a fixed clamping jaw and a movable clamping jaw which are biased toward each other by screws or other means to grip the electrical cable. Examples of this type of electrical device are shown in U.S. Pat. Nos. 4,046,961 to Hoffman; 3,784,961 to Gartland Jr.; 3,605,059 to Lipinski; and 3,856,371 to Poliak et al. Of these prior art devices, only U.S. Pat. No. 3,784,961 to Gartland is specifically directed to a clamp assembly capable of accommodating cables of different diameters. The clamp assembly disclosed in that patent includes a recess in the fixed jaw and a recess in the movable jaw which together accommodate large size cables. An insert can be inserted into the recess of the fixed jaw to reduce the dimension of the passageway between the jaws so as to effectively grip the cable. Although this structure utilizing the insert effectively grips cables of different diameters, it is necessary to remove the movable jaw from the assembly to remove the insert. Once the insert is removed from the jaw, the insert is usually lost or discarded, which prevents the jaw from accommodating a small size cable. Since the insert fits loosely in the clamping jaw, it tends to become separated from the clamping jaw during shipping. Finally, failure to remove the insert when clamping a large size cable may result in damage to the cable or the connector.
The above-noted devices demonstrate a continuing need in the art for an electrical device that is able to accommodate different size electrical cables. There is further a need for electrical devices where the assembly for accommodating different size cables is captively retained with the main body of the device to prevent loss of components.